George W. Bush did it in 2000. So did John Quincy Adams, Rutherford B. Hayes and Benjamin Harrison.

Could President Obama be next?

It's not often that a presidential candidate wins the election while losing the popular vote, but polling suggests it could happen again in 2012 if the race tightens just a bit.

A handful of new polls today show President Obama leading in important battleground states. Surveys by CBS-New York Times-Quinnipiac rate him ahead in Virginia (50-46 percent) and Wisconsin (51-45 percent), while erasing a Romney lead in Colorado to pull ahead narrowly (48-47 percent).

The last batch of swing-state polls, released Thursday by NBC/Wall Street Journal/Marist, showed Obama leading in Ohio (50-43 percent), Florida (49-44 percent) and Virginia.

Get more pure politics at ABCNews.com/Politics and a lighter take on the news at OTUSNews.com .

That's good news for Obama, and if the election were held today, they indicate that Obama would be the favorite.

But national polling remains very close. Since Romney secured his party's nomination in April, neither candidate has gained much separation.

President Obama's single-digit convention bounce has mostly evaporated. ABC News-Washington Post polling showed him leading Mitt Romney 50-44 percent after the conventions, and Gallup's daily tracking poll concurred. Now, Gallup shows the two candidates virtually tied: Obama leads 47-46 percent, the exact same numbers Gallup reported as the GOP convention began in Tampa.

ABC News' Matthew Dowd ran some numbers in June on how Obama could win the election despite an across-the-board fall from 2008:

… Obama won the popular vote by a national percentage of just over 7 points in 2008. If we subtract 8 points from the margin in every state, Romney would have a little less than a 1-point victory nationally (which gives you the 1 million vote margin for him in the popular vote).

And as we subtract 8 points from every state's margin, what happens to the electoral college? It gets much, much closer, but Obama still wins it by six electoral votes. So in one very possible scenario, Obama can lose the popular vote and still be re-elected because he barely carries the electoral college.

In 2012, Obama can expect slippage in states he won in 2008. In Wisconsin, a state where Romney's campaign has begun airing ads after the selection of Wisconsin Rep. Paul Ryan as VP candidate, Obama won by 13 percentage points in 2008 but now leads by six, according to CBS/New York Times/Quinnipiac. In New Mexico, Obama won by 15 percentage points in 2008, but a recent Albuquerque Journal survey showed him leading by five. He won Michigan by 16 percentage points in 2008, a margin that could be tough to replicate.

After winning Indiana, Colorado and North Carolina in 2008, Obama could lose those states in 2102 while still winning the election, if big states like Ohio and Florida swing his way in November, as the recent polls indicate. Missouri, which narrowly selected Sen. John McCain in 2008, is expected to vote safely for Romney in 2012.

In the large, Democratic states of California and New York, Obama hasn't seen much of a decline. His 2008 vote margins of 24 and 27 percentage points, respectively, remain virtually unchanged, according to recent polls from Field Research and Quinnipiac.

But at various points in the election cycle, polls have shown Republicans more excited about voting in November 2012 than Democrats. If a lagging economy and a lack of excitement deflate Obama's vote totals in safely Democratic states, boost Romney's total in red states, and makes swing states more competitive, Obama could surpass 269 Electoral College votes while seeing Romney become the next Al Gore.